Machine gun texting 

Sending off several text messages in rapid succession without waiting for a reply to one.

My girlfriend is machine gun texting me to death and it is pissing me off

Machine gun texting by Sinolop April 15, 2013

Machine gun texting 

Texting people a couple words at a time in separate messages

Hey
<send>
are you here?
<send>
I can't find you.
<send>
I'm at the front door.
<send>
- Response

Stop machine gun texting me, I'll be there in just a second. Jeeze! You can send all that in one message you know.
<Send>

Machine gun texting by cdpage January 7, 2012